In August and November 2022 Patently Apple posted two patent reports describing a possible future glass bodied MacBook. Apple described using a bendable glass in the keyboard area. Apple's patent FIG. 2A below depicts an example distribution of locally-flexible regions defined into an interior surface of an electronic device that may be associated with a force input/haptic output interface. More specifically, Apple notes that the force input/haptic output interface #1200 also includes a haptic actuator #1214 that can include a piezoelectric element. As a result of this construction, an actuation of the force transducer induces a bending moment into the support structure to generate a haptic output through the external surface.
As noted in patent FIG. 3 above we're able to see that with a glass design, the new force input/haptic output actuators could be spread out over the width of a future MacBook that would reduce the thickness of the MacBook while eliminating the traditional cutout region for a dedicated trackpad.
At last week's CES 2023 Apple supplier LG showed off a next-gen notebook design based on using Corning Gorilla Glass. One of the cool features of their 'LG Gram' notebook is having no visible trackpad. When a user passes a finger on the trackpad area, lights beneath the glass light up to illustrate the trackpad area as presented in the video clip from Engadget. This is definitely a possible feature for a glass MacBook so as to provide it with a clean design.
With Apple's engineering teams working on a possible future glass MacBook, seeing the LG Gram introduce the hidden trackpad feature just made the likelihood of a future Glass MacBook all that more plausible. It confirmed that glass could be a new emerging trend for PC's and notebooks and that Apple is on top of this trend.
Whether Apple would use a hybrid metal and glass embodiment is unknown at this time, but a next-gen MacBook model with some real innovation in design would be a great addition to the MacBook family.